isMaryspeaking的精選

問題詳情：根據對話內容在空白處填入適當的詞語。A: （1） ,DuLing! （2） isMaryspeaking.B:Hi,Mary.A:I （3） youyesterdayafternoon,but （4）  athome.B:Oh,（5） .Iwenttothe （6）  intownyesterday.A:Isthebiggestsciencem...